MAINT: SciPy 1.12.0 "final" backports/prep

[tylerjereddy]

• a few version changes to set us at 1.12.0 "unreleased" (the latter flag gets switched at the exact moment I do the release); delete the "is not released" disclaimer in the release notes
• update release notes after the backports

Backports included so far:

1. DOC: 1.12 release notes tweaks #19877
2. DEP: extend some announced deprecations due to out-of-band 1.13 release #19892
3. DEP: reflect extended deprecations also in release notes #19903
4. BLD: ensure the name of the installed scipy package is lower-case #19910 (manual resolution of merge conflict)
5. Revert "ENH: stats.wasserstein_distance: multivariate Wasserstein distance/EMD #19881

TODO:

• known issue, maybe we let it slide since pytest RC (for now): MAINT: 1.12.x series tests still fail with pytest 8.0.0rc1 #19847
• need decision on this revert I think: Revert "ENH: stats.wasserstein_distance: multivariate Wasserstein distance/EMD #19881
• 1 flush of the wheel builds in CI for testing when we're ready, before the final release process starts

[tylerjereddy]

The CI was green. I've now added the one extra reversion from stats to the backport list above and cherry-picked it in here (along with deleting the release note entry for that reversion target).

The full suite + doc build was still passing locally after that/updating the relnotes, so I've initiated a test run of the full wheel build matrix here. If that passes, then 1.12.0 "final" should be imminent.

[lucascolley]

sounds like the sphinx theme update is still waiting for 1.12.1 then? FWIW it does look ready, but I suppose no big rush.

[tylerjereddy]

Yes, I created the 1.12.1 milestone just now. Let's see if I can get 1.12.0 out the door today.